In a proclamation addressed to the "People of Maryland," dated September 8, 1862, Confederate general Robert E. Lee explains why his Army of Northern Virginia has undertaken an invasion of their state. Hoping to appeal to the slaveholding and Confederate-leaning citizens of Maryland, Lee refers to them as being "allied to the States of the South by the strongest social, political and commercial ties"; he goes on to accuse the North of having turned Maryland into a "conquered Province." Lee writes that the Confederate army is there to aid "in throwing off this foreign yoke" of Union oppression and to help "regain the rights of which you have been despoiled."
The stated mission failed. Greeted without the expected enthusiasm from Maryland's citizens, Lee's army then suffered the disadvantage of being on hostile territory for the first time in the war. Less than two weeks after this proclamation, Lee was in retreat. The bloody Battle of Antietam took place on September 17, and the following day Lee's army began moving across the Potomac River, back to Confederate territory. The invasion had been a high-stakes gamble that failed.